Kiln cooling system

Abstract

The utility model discloses a kiln cooling system relates to kiln cooling technical field, and kiln cooling system includes: kiln structure, waste heat boiler and steam water heat exchanger, and kiln structure, waste heat boiler and steam water heat exchanger are communicated in proper order, and steam water heat exchanger has flue gas discharge port, steam buffer tank and refrigerating unit, steam buffer tank and refrigerating unit all are set up to be selectively communicated in waste heat boiler and steam water heat exchanger respectively, to make refrigerating unit form two -level cold flow supply structure when being communicated in waste heat boiler and steam water heat exchanger respectively, and make steam buffer tank form two -level hot flow supply structure when being communicated in waste heat boiler and steam water heat exchanger respectively. The kiln cooling system of the utility model can realize double -heat source type's heat absorption utilization, to make the heat of absorption can be used for refrigerating unit's cold water making, also can store through steam buffer tank, is convenient for using at any time, reduces the overheating damage of heat to kiln structure connection's electric instrument equipment.

Description

Technical Field

[0001] This utility model relates to the field of kiln cooling technology, and in particular to a kiln cooling system. Background Technology

[0002] With the rapid development of the new energy industry, the production capacity of lithium battery cathode materials continues to expand, with high-temperature furnaces widely used in processes such as precursor synthesis and sintering. These furnaces continuously emit large amounts of high-temperature flue gas during operation, with temperatures typically reaching 600℃. This high-temperature flue gas not only directly wastes energy but also exacerbates the temperature in the work area, significantly negatively impacting personnel and equipment. Due to flue gas accumulation and thermal radiation effects, the ambient temperature can reach approximately 45-60℃, leading to frequent equipment failures and severe energy waste, indicating room for improvement. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a kiln cooling system that enables the effective utilization of kiln heat.

[0004] A kiln cooling system according to an embodiment of the present invention includes: a kiln structure; a waste heat boiler and a steam-water heat exchanger, wherein the kiln structure, the waste heat boiler, and the steam-water heat exchanger are sequentially connected, and the steam-water heat exchanger has a flue gas discharge port; a steam buffer tank and a refrigeration unit, wherein the steam buffer tank and the refrigeration unit are both configured to be selectively connected to the waste heat boiler and the steam-water heat exchanger respectively, so that the refrigeration unit forms a two-stage cold flow supply structure when connected to the waste heat boiler and the steam-water heat exchanger respectively, and the steam buffer tank forms a two-stage heat flow supply structure when connected to the waste heat boiler and the steam-water heat exchanger respectively.

[0005] According to the kiln cooling system of this utility model embodiment, by setting the waste heat boiler and steam-water heat exchanger to be selectively connected to the steam buffer tank and the refrigeration unit respectively, the connection switching under different heat utilization needs can be met, thereby satisfying the heat utilization needs and realizing dual heat source heat absorption and utilization. The absorbed heat can be used for the production of chilled water in the refrigeration unit, or it can be stored in the steam buffer tank for easy use at any time, reducing the overheating damage of heat to the electrical and instrumentation equipment connected to the kiln structure.

[0006] According to some embodiments of the present invention, the kiln cooling system includes a refrigeration unit comprising a steam-driven unit and a hot water-driven unit. The steam-driven unit is selectively connected to the waste heat boiler, and the hot water-driven unit is selectively connected to the steam-water heat exchanger, so as to jointly form the secondary cold flow supply structure.

[0007] According to some embodiments of the present utility model, the kiln cooling system further includes a first cold water buffer tank. The first cold water buffer tank is provided with a first cold water inlet and a first cold water outlet. The first cold water inlet is connected to the outlet of the steam-driven unit, and the first cold water outlet is used to deliver cold water to the outside. And / or, the refrigeration unit further includes a second cold water buffer tank, the second cold water buffer tank having a second cold water inlet and a second cold water outlet, the second cold water inlet being connected to the outlet of the hot water drive unit, and the second cold water outlet being used to deliver cold water to the outside.

[0008] According to some embodiments of the present utility model, the kiln cooling system further includes a chilled water supply path and a kiln area cooling water path. The first cold water outlet is connected to the chilled water supply path and the kiln area cooling water path respectively, and the second cold water outlet is connected to the kiln area cooling water path. The cooling water circuit in the kiln area is connected to at least one of a fan coil unit, a heat sink, a cold air box, and a dehumidification pipe.

[0009] The kiln cooling system according to some embodiments of the present invention further includes a flash evaporator, wherein the outlet end of the waste heat boiler is adapted to be selectively connected to the inlet end of the steam buffer tank, and the outlet end of the steam-water heat exchanger is adapted to be selectively connected to the inlet end of the steam buffer tank through the flash evaporator.

[0010] The kiln cooling system according to some embodiments of the present invention also includes a steam-using device connected to the steam outlet of the steam buffer tank.

[0011] According to some embodiments of the present invention, the kiln cooling system includes at least two kiln bodies, and the at least two kiln bodies are respectively connected to the waste heat boiler.

[0012] According to some embodiments of the present invention, in the kiln cooling system, an exhaust fan is connected to the flue gas discharge port.

[0013] According to some embodiments of the present invention, the kiln cooling system is provided with a filter device at the flue gas outlet; and / or, a flue gas duct is connected between the kiln structure and the waste heat boiler, and the flue gas duct is constructed as a double-layer duct.

[0014] The kiln cooling system according to some embodiments of the present invention further includes a control module, which is configured to control the steam buffer tank to be connected to the waste heat boiler and the steam-water heat exchanger respectively in a first seasonal mode, and to control the refrigeration unit to be connected to the waste heat boiler and the steam-water heat exchanger respectively in a second seasonal mode.

[0015] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the kiln cooling system in the first season mode according to an embodiment of this utility model; Figure 2 This is a schematic diagram of the kiln cooling system in the second season mode according to an embodiment of the present invention; Figure 3 This is a flowchart illustrating the working principle of the kiln cooling system according to an embodiment of this utility model. Figure label: Kiln cooling system 100, Phase I kiln 11, Phase II kiln 12, waste heat boiler 13, steam-water heat exchanger 14, exhaust fan 15. Steam-driven unit 21, hot water-driven unit 22, first cold water buffer tank 23, second cold water buffer tank 24, chilled water makeup line 25, kiln area cooling water line 26 Steam buffer tank 31, flash evaporator 32, steam-using equipment 33 Detailed Implementation The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0017] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0018] The following is for reference. Figures 1-3 The present invention describes a kiln cooling system 100 according to an embodiment of the present invention. The kiln cooling system 100 can effectively utilize the heat generated by the kiln structure and can form different types of heat utilization methods to meet the heat use needs under different application scenarios.

[0019] like Figures 1-2 As shown, the kiln cooling system 100 according to some embodiments of the present invention includes: a kiln structure, a waste heat boiler 13, a steam-water heat exchanger 14, a steam buffer tank 31, and a refrigeration unit.

[0020] The kiln structure includes the kiln body, which can be one, two, or more, such as... Figure 1 and Figure 2 As shown, the kiln structure may include a first-stage kiln 11 and a second-stage kiln 12. The main body of the kiln is used for the processing of positive electrode materials for lithium batteries, and a large amount of high-temperature flue gas is generated during the operation of the kiln body. For example, each kiln body can generate 4000m³ / h of flue gas at 600℃, which means that the high-temperature flue gas carries a large amount of heat.

[0021] The kiln structure, waste heat boiler 13, and steam-water heat exchanger 14 are connected in sequence. This allows the high-temperature flue gas generated in the kiln structure to first enter the waste heat boiler 13 and then be transported from the waste heat boiler 13 to the steam-water heat exchanger 14. When the high-temperature flue gas passes through the waste heat boiler 13, it can utilize thermal energy to generate saturated steam, reducing the flue gas temperature to approximately 200°C. The generated steam can be utilized, transferring some of the heat from the high-temperature flue gas to the steam, converting a low-grade heat source into a high-grade heat source. Simultaneously, the 200°C medium-temperature flue gas can enter the steam-water heat exchanger 14 to exchange heat with the circulating water in the steam-water heat exchanger 14, producing 90°C hot water. This hot water can also be utilized. Furthermore, the steam-water heat exchanger 14 has a flue gas discharge port, ensuring that the temperature of the flue gas after heat exchange is reduced to approximately 80°C or lower, meeting emission requirements.

[0022] Both the steam buffer tank 31 and the refrigeration unit are configured to be selectively connected to the waste heat boiler 13 and the steam-water heat exchanger 14, respectively. In other words, the steam buffer tank 31 can be configured to be connected to both the waste heat boiler 13 and the steam-water heat exchanger 14, and the refrigeration unit can also be configured to be connected to both the waste heat boiler 13 and the steam-water heat exchanger 14, respectively. The specific connection method can be flexibly set according to actual usage requirements, such as temperature requirements or seasonal requirements. For example, in spring and summer, when the cooling demand is large, the heat from the flue gas in the waste heat boiler 13 and the steam-water heat exchanger 14 can be used for cooling. Or, in autumn and winter, when the heating demand is large, the heat from the flue gas in the waste heat boiler 13 and the steam-water heat exchanger 14 can be used for heating, or it can also be used to meet other heat requirements.

[0023] When the refrigeration unit is connected to both the waste heat boiler 13 and the steam-water heat exchanger 14, the kiln cooling system 100 can form a two-stage cold flow supply structure. This means the heat from the flue gas in the waste heat boiler 13 can be directly applied to the refrigeration unit. In other words, the steam generated in the waste heat boiler 13 can be used to power the refrigeration unit, driving it to produce chilled water. Simultaneously, the hot water from the steam-water heat exchanger 14, after heat exchange with the flue gas, can also be used to power the refrigeration unit, driving it to produce chilled water. Thus, a dual-heat-source absorption refrigeration unit can be actively powered.

[0024] The refrigeration unit can be configured as a lithium bromide absorption chiller.

[0025] Furthermore, when the steam buffer tank 31 is connected to both the waste heat boiler 13 and the steam-water heat exchanger 14, the kiln cooling system 100 forms a two-stage heat supply structure. This means that the heat from the flue gas in the waste heat boiler 13 can be stored in the steam buffer tank 31 as high-temperature steam, and then used as needed. For example, the steam-using equipment 33 can be connected to the steam buffer tank 31 to utilize the heat from the steam. Similarly, dual-heat-source absorption-type heat storage and utilization can be achieved.

[0026] Therefore, effectively and rationally utilizing the high-temperature flue gas generated by the kiln structure can not only reduce heat waste and improve energy efficiency, thus responding to the policy requirements of energy conservation, emission reduction, and carbon neutrality, but also prevent the heat in the high-temperature flue gas from forming a large area of ​​thermal radiation temperature in the kiln area, reducing the aging rate of electronic components in the kiln area, reducing the failure rate, and ensuring the overall stable operation of the kiln.

[0027] According to the kiln cooling system 100 of this utility model embodiment, by setting the waste heat boiler 13 and the steam-water heat exchanger 14 to be selectively connected to the steam buffer tank 31 and the refrigeration unit respectively, the connection switching under different heat utilization needs can be met, thereby meeting the heat utilization needs and realizing dual heat source heat absorption and utilization. The absorbed heat can be used for the production of chilled water in the refrigeration unit, or it can be stored in the steam buffer tank 31 for easy use at any time, thereby reducing the overheating damage of heat to the electrical and instrumentation equipment connected to the kiln structure.

[0028] In some embodiments, the refrigeration unit includes a steam-driven unit 21 and a hot water-driven unit 22. The steam-driven unit 21 is selectively connected to the waste heat boiler 13, and the hot water-driven unit 22 is selectively connected to the steam-water heat exchanger 14, so as to jointly form a two-stage cold flow supply structure, thereby enabling the heat from the two heat sources to be applied to the production of cold water from different refrigeration units, and realizing the production of cold water in different temperature ranges.

[0029] When there is a demand for cold water supply, the waste heat boiler 13 can be connected to the steam drive unit 21 so that the steam in the waste heat boiler 13 can enter the steam drive unit 21. For example, the waste heat boiler 13 can provide 7 bar saturated steam (about 500 kg / h) to the steam drive unit 21, thereby enabling the steam drive unit 21 to perform work to produce cold water. The produced cold water can be controlled within 7℃–12℃. At the same time, the steam-water heat exchanger 14 can also be connected to the hot water drive unit 22 so that the hot water produced by the steam-water heat exchanger 14 can enter the hot water drive unit 22. For example, the steam-water heat exchanger 14 can provide 90℃ hot water (about 1.7 t / h) to the hot water drive unit 22, thereby enabling the hot water drive unit 22 to perform work to produce cold water. The produced cold water can be controlled within 12℃–25℃.

[0030] Both the steam-driven unit 21 and the hot water-driven unit 22 can be configured as lithium bromide absorption chillers.

[0031] Therefore, the steam-driven unit 21 and the hot water-driven unit 22, driven by different heat sources, can be used to produce chilled water in different temperature ranges, so that chilled water at different temperatures can meet the needs of different application scenarios.

[0032] In some embodiments, the refrigeration unit further includes a first chilled water buffer tank 23, which has a first chilled water inlet and a first chilled water outlet. The first chilled water inlet is connected to the outlet of the steam-driven unit 21, and the first chilled water outlet is used to supply chilled water externally. This allows the chilled water produced by the steam-driven unit 21 to be stored in the first chilled water buffer tank 23, enabling the first chilled water buffer tank 23 to selectively supply chilled water to the outside. Specifically, the first chilled water buffer tank 23 can temporarily store chilled water produced by the steam-driven unit 21 at temperatures between 7°C and 12°C. Therefore, when chilled water is not in use, it can be temporarily stored in the first chilled water buffer tank 23 for later use. When chilled water is needed, it can be used directly, or the chilled water produced by the steam-driven unit 21 can be used directly after passing through the first chilled water buffer tank 23, making the application more flexible.

[0033] And / or, in some embodiments, the refrigeration unit further includes a second cold water buffer tank 24, which has a second cold water inlet and a second cold water outlet. The second cold water inlet is connected to the outlet of the hot water drive unit 22, and the second cold water outlet is used to supply cold water externally. This allows the cold water produced by the hot water drive unit 22 to be stored in the second cold water buffer tank 24, enabling the second cold water buffer tank 24 to selectively supply cold water to the outside. Specifically, the second cold water buffer tank 24 can temporarily store cold water produced by the hot water drive unit 22 within the range of 12℃–25℃. Therefore, when cold water is not in use, it can be temporarily stored in the second cold water buffer tank 24 for later use. When cold water is needed, the cold water in the second cold water buffer tank 24 can be used directly, or the cold water produced by the hot water drive unit 22 can be used directly after passing through the second cold water buffer tank 24, making the usage more flexible.

[0034] In actual design, the first cold water buffer tank 23 and the second cold water buffer tank 24 can be set as two independent tanks, or they can be set as a whole with a heat insulation structure between them. The setting method is flexible and can be selected.

[0035] In some embodiments, the refrigeration unit further includes a chilled water supply path 25 and a kiln area cooling water path 26; wherein, the chilled water supply path 25 may be configured to be connected to the chilled water system to supply chilled water to the chilled water system, thereby reducing the refrigeration load on the compressor, and the kiln area cooling water path 26 may perform local or large-scale cooling on the end of the kiln area, thereby realizing the conversion of heat to cold in the kiln area, that is, directly cooling to the work area, thereby reducing the instability of the working environment in the kiln area.

[0036] The first cold water outlet is connected to the chilled water replenishment water path 25 and the kiln area cooling water path 26, respectively. That is, the cold water produced by the steam-driven unit 21 can be transported from the first cold water outlet to the chilled water replenishment water path 25, or to the kiln area cooling water path 26, so that the cold water within the range of 7℃–12℃ can be used for different application paths.

[0037] It should be noted that when supplying cold water, priority should be given to supporting the cooling of the work area. That is, the first cold water outlet should be connected to the cooling water circuit 26 in the kiln area first. After meeting the cooling needs of the work area end in the kiln area, the water from the first cold water outlet should be supplied to the chilled water replenishment circuit 25 to replenish the chilled water system.

[0038] Furthermore, the second cold water outlet is connected to the kiln area cooling water path 26, meaning that the cold water produced by the hot water drive unit 22 can flow from the second cold water outlet to the kiln area cooling water path 26, so that the cold water is supplied to the end of the kiln area, thereby meeting the cooling needs of the end of the kiln area.

[0039] The kiln area cooling water path 26 is connected to at least one of a fan coil unit, a heat sink, a cold air box, and a dehumidification pipeline. The cold water in the kiln area cooling water path 26 can be applied to the fan coil unit at the end of the kiln area, or to the heat sink, or to the cold air box, or to the dehumidification pipeline.

[0040] Therefore, the cold water in the cooling water path 26 of the kiln area can be blown out as cold air by the fan coil unit, which is suitable for the personnel working area; and, low-temperature heat sinks can be arranged under the equipment or on the wall to remove heat through natural convection, which is suitable for static equipment areas; and when connected to the cold air box, it can be used for electrical equipment, with cold water cooling the equipment through heat exchange tubes and then being sent into the equipment through the fan for cooling; or, a dehumidification system can be added to the air outlet bypass, which can detect the humidity of the cold air and switch the dehumidification pipeline when the humidity exceeds the standard, and adjust the moisture in the cold air through rotating dehumidification to meet the dew point requirements of the cathode material kiln area.

[0041] Therefore, by using various cooling methods, we can ensure that each position and piece of equipment can be effectively cooled without interfering with the process flow.

[0042] In some embodiments, the kiln cooling system 100 further includes a flash evaporator 32, the outlet of the waste heat boiler 13 is adapted to be selectively connected to the inlet of the steam buffer tank 31, and the outlet of the steam-water heat exchanger 14 is adapted to be selectively connected to the inlet of the steam buffer tank 31 via the flash evaporator 32. Thus, the steam generated in the waste heat boiler 13 can directly enter the steam buffer tank 31 for storage, while the high-temperature hot water in the steam-water heat exchanger 14 can enter the flash evaporator 32 to form steam, which is then stored in the steam buffer tank 31. This achieves two-stage steam collection and storage.

[0043] The 7-bar saturated steam (approximately 500 kg / h) generated in the waste heat boiler 13 can directly enter the steam buffer tank 31 from the inlet end of the steam buffer tank 31. At the same time, the 90℃ hot water (approximately 1.7 t / h) in the steam-water heat exchanger 14 enters the flash evaporator 32 to form steam, which then enters the steam buffer tank 31. Thus, steam collection and storage can be achieved through two paths, realizing heat recovery and utilization.

[0044] In some embodiments, the kiln cooling system 100 further includes a steam-using device 33, which is connected to the steam outlet of the steam buffer tank 31. The steam-using device 33 can be a steam-using device within the plant area or an additional steam-using device, which helps to increase the scope of steam use.

[0045] Among them, the steam-using equipment 33 can be a dehumidifier, a vibration drying device, etc., so that the steam in the steam buffer tank 31 can be directly used for air dehumidification in the dehumidifier, thereby realizing the direct utilization of steam. In addition, when steam is used in the steam-using equipment 33 within the plant area, the purchase of external steam can be reduced, thus lowering the operating cost.

[0046] In some embodiments, the kiln structure includes at least two kiln bodies, each connected to the waste heat boiler 13. This allows for the configuration of two, three, or more kiln bodies, ensuring that the high-temperature flue gas generated by different numbers of kiln bodies can be transported to the waste heat boiler 13. In other words, when different kiln bodies generate high-temperature flue gas, it can be directed towards the waste heat boiler 13 at different times or frequencies to meet the emission requirements of more high-temperature flue gas. Simultaneously, it enables centralized collection and treatment of high-temperature flue gas from different numbers of kiln bodies, achieving the reuse of heat utilization components and reducing installation costs.

[0047] Specifically, such as Figure 1 and Figure 2 As shown, the kiln structure includes two kiln bodies, namely the first-stage kiln 11 and the second-stage kiln 12. The first-stage kiln 11 and the second-stage kiln 12 are respectively connected to the waste heat boiler 13. This allows one of the kiln bodies to discharge high-temperature flue gas into the waste heat boiler 13, or both kiln bodies to discharge high-temperature flue gas into the waste heat boiler 13 simultaneously, thereby achieving flexibility in heat utilization.

[0048] In some embodiments, an exhaust fan 15 is connected to the flue gas outlet. By setting the exhaust fan 15, the emission efficiency of the flue gas at the flue gas outlet can be increased, and the efficiency of heat collection can be improved.

[0049] Furthermore, the exhaust fan 15 accelerates the emission of flue gas at the flue gas outlet, enabling the flue gas to be emitted to a more distant area, thus achieving directional emission of the flue gas.

[0050] In some embodiments, a filtration device is provided at the flue gas outlet to filter the discharged flue gas and ensure its cleanliness. The filtration device can be a mechanical dust removal device, such as one that uses physical principles like gravity or centrifugal force to separate particulate matter, such as a cyclone dust collector and a gravity settling chamber; the filtration device can also be a filtration-type dust removal device, such as one that uses porous media (such as filter bags or filter cartridges) to trap dust, a typical example being a bag filter, which can achieve a filtration efficiency of up to 99.97% for particles larger than 0.3 μm.

[0051] And / or, a flue gas duct connects the kiln structure and the waste heat boiler 13, allowing the high-temperature flue gas emitted from the kiln structure (the combined 4000 m³ / h, 600°C flue gas from the two kiln main bodies to 8000 m³ / h, 600°C high-temperature flue gas) to be guided to the waste heat boiler 13 through the flue gas duct. The flue gas duct is constructed as a double-layer pipe. If the flue gas duct is designed with a double-layer insulation structure, wrapped with rock wool or ceramic fiber, heat loss is reduced, ensuring that the heat of the flue gas entering the waste heat boiler 13 meets the requirements for steam production.

[0052] In some embodiments, the kiln cooling system 100 further includes a control module, which is configured to control the steam buffer tank 31 to be connected to the waste heat boiler 13 and the steam-water heat exchanger 14 respectively in the first seasonal mode, and to control the refrigeration unit to be connected to the waste heat boiler 13 and the steam-water heat exchanger 14 respectively in the second seasonal mode. Thus, the selective connection between the various components in the two seasonal modes can be realized through the control module to adapt to the heat or cooling needs of different seasons.

[0053] The first seasonal mode can be autumn, winter, or both. In this mode, the steam buffer tank 31 collects the steam generated by the waste heat boiler 13, the steam-water heat exchanger 14, and the flash evaporator 32, and supplies heat through the steam stored in the steam buffer tank 31, thus meeting the heating and dehumidification needs in autumn and winter. The second seasonal mode can be spring, summer, or both. In this mode, the refrigeration unit is thermally driven by the steam generated by the waste heat boiler 13 and the hot water generated by the steam-water heat exchanger 14 to produce chilled water, thus meeting the chilling needs in spring and summer.

[0054] Specifically, during the spring and summer operation mode, the high-temperature flue gas generated by the kiln body enters the waste heat boiler 13 through collection and guidance pipes. The waste heat boiler 13 generates 7 bar steam (steam drives the lithium bromide absorption chiller to drive the heat source) and 200°C flue gas, which enters the steam-water heat exchanger 14 to generate 90°C hot water (hot water drives the lithium bromide absorption chiller to drive the heat source). The steam drives the low-temperature absorption chiller unit to produce 7–12°C chilled water for end-point cooling and chilled water replenishment. The hot water drives the medium-temperature absorption chiller unit to produce 12–25°C chilled water, which is directly delivered to the cooling end. Through two chilled water buffer tanks and a distribution system, chilled water is preferentially delivered to the work stations according to demand, and the remaining chilled water is incorporated into the chilled water system to form a closed-loop path of high-temperature flue gas → staged heat exchange → dual-path absorption refrigeration → staged chilled water output → kiln cooling / chilled water replenishment.

[0055] Furthermore, during the autumn and winter operation mode, the high-temperature flue gas generated by the kiln body enters the waste heat boiler 13 through collection and guidance pipelines; the 7-bar steam generated by the waste heat boiler 13 is directly delivered to the steam-using equipment 33 in the plant area (such as dehumidifiers, vibration drying equipment, etc.), replacing the purchased steam; the 90°C hot water produced by the steam-water heat exchanger 14 is converted into steam through the flash evaporator 32 and used by other steam-using equipment 33, realizing direct supply of waste heat; avoiding the idling of the refrigeration unit in autumn and winter, improving the utilization rate of waste heat, and reducing the cost of purchased steam, so as to form a closed loop path of high-temperature flue gas → evaporator flash evaporation → 7-bar 200°C steam → use of equipment such as dehumidifier heat exchange and vibration drying heat exchange → energy saving (autumn and winter) by reducing the amount of purchased steam used in the factory.

[0056] In this way, during spring and summer, the originally ineffective flue gas heat energy is converted into a dual heat source (steam + hot water) that can drive the heat pump system through the staged heat exchange system for workplace cooling and chilled water system replenishment; during autumn and winter, the refrigeration system is shut down, and the steam generated by the waste heat boiler 13 is directly supplied to the steam-using equipment 33 in the plant area (such as dehumidifiers, vibration dryers, etc.), and the hot water produced by the steam-water heat exchanger 14 is converted into steam through flash evaporation for use by other steam-using equipment 33, thereby saving the plant's external steam consumption, improving energy utilization efficiency, and responding to the policy requirements of energy conservation, emission reduction and carbon neutrality.

[0057] It should be noted that the control module (PLC) switches control logic in different seasons: The control module can automatically switch the operating mode according to the set season, ambient temperature, or work station temperature requirements: in spring and summer, the cooling mode is given priority, and the cold source supplies the work station and the chilled water system; in autumn and winter, the chiller is turned off, and the system switches to the direct steam supply mode, and automatically adjusts the steam distribution ratio to ensure the stable operation of the steam-using equipment 33. This makes the kiln cooling system 100 have strong overall and modular characteristics. The flue gas treatment, heat energy conversion, absorption refrigeration and cold source distribution form a linkage mechanism, and the "work station priority, surplus supplement" operation strategy is realized through PLC intelligent control, which is convenient for unified deployment and centralized management, and is suitable for promotion and application in high-temperature industrial areas such as cathode materials.

[0058] The specific control procedures for spring and summer are as follows: like Figure 3 As shown, after the system starts, the control module (PLC) host initializes. At this time, the equipment status can be checked first. If the equipment is faulty, an alarm will be triggered and the system will be stopped. If the equipment is normal, data acquisition will be performed, that is, continuous temperature detection will be performed. Furthermore, it determines whether the point temperature exceeds the set value. If it does not exceed the set value, it maintains the current state. If it exceeds the set value, it adjusts the chiller unit to use chilled water for cooling. It also determines whether the point temperature drops to the set value. If it does not drop to the set value, it continues to adjust the chiller unit to use chilled water for cooling. If it drops to the set value, it determines whether the chilled water supply is sufficient. If it is insufficient, it maintains the current chilled water flow rate. If it is sufficient, it puts the excess chilled water into the chilled water system for utilization.

[0059] Therefore, the heat of the high-temperature flue gas in the kiln structure can be rationally utilized, and the kiln cooling system 100 of this utility model embodiment has the following technical advantages: 1) Significantly improves the high-temperature working environment: The system can precisely deliver medium-temperature chilled water (12–25℃) to the kiln work area through fan coil units, cold air boxes, and other terminal devices, reducing the temperature in the working area from the original high of 45-60℃ to below 40℃. Compared with traditional fans and water curtain walls, it has higher cooling efficiency, wider coverage, does not increase air humidity, does not interfere with the sintering process environment, and greatly improves personnel comfort and safety.

[0060] 2) Effectively reduce equipment failure rate: Install a closed cold air box system near key equipment such as electrical cabinets and instrument control boxes to effectively suppress high temperature heat radiation and internal temperature rise, delay the aging of components, reduce failures such as short circuits, malfunctions, and burnouts caused by high temperature, and significantly improve production stability and equipment life.

[0061] 3) Achieve efficient and graded recovery of high-temperature flue gas: After purification, the flue gas enters the graded heat exchange system. One part generates 7 barg steam to drive the low-temperature unit, and the other part generates 90℃ hot water to drive the medium-temperature unit. This achieves the cascade utilization of a single high-temperature flue gas heat source, significantly improving energy efficiency and reducing energy waste and carbon emissions caused by direct emissions.

[0062] 4) Save energy in the refrigeration system: After the 7-12℃ chilled water produced by the low temperature unit meets the cooling needs of the terminal points, the excess water is fed into the factory's chilled water main pipe to replace the compressor's refrigeration load, reducing power consumption and bringing considerable savings in operating costs.

[0063] 5) Intelligent control strategy with priority given to specific positions: The control module can monitor the temperature at specific points in real time and automatically adjust the opening of the distribution valve to achieve the "priority given to specific positions, with reserve supplementation" operation strategy, ensuring that the cooling target in the core area is stably achieved.

[0064] 6) Modular and highly integrated design: Flue gas collection, purification, heat exchange, dual-path heat pump, cold water buffer and terminal cooling modules can be flexibly laid out according to site conditions, suitable for new or renovation projects, with high system integration, short installation cycle, convenient maintenance, and cross-industry adaptability.

[0065] 7) High safety and process compatibility: Flue gas is only used for heat exchange and does not flow back to the main process line; the cold source system is a closed water circulation system to prevent leakage and pollution, and does not affect the stability of the original kiln and sintering process.

[0066] 8) Industry-first and promotional value: In the cathode material industry, it is the first to propose a complete solution to convert the waste heat of kiln flue gas into a graded cold source through dual heat source absorption refrigeration technology, realizing on-site cooling and chilled water replenishment. This fills a gap in the industry and can provide a replicable energy-saving cooling model for other high-temperature industries such as metallurgy and building materials.

[0067] 9) Seasonal waste heat utilization: In autumn and winter when cooling is not required, the waste heat boiler 13 directly supplies steam to the dehumidifier, and the steam-water heat exchanger 14 directly supplies hot water to the bathroom, etc., reducing the consumption of purchased steam and heating energy, and further improving the system's energy utilization rate.

[0068] 10) Significantly improved operational flexibility and economy: The system can automatically switch modes according to ambient temperature, month or production needs, to achieve continuous and efficient utilization of waste heat throughout the year, saving a lot of steam procurement costs and electricity bills every year.

[0069] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0070] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A kiln cooling system, characterized in that, include: Kiln structure; Waste heat boiler (13) and steam-water heat exchanger (14), the kiln structure, the waste heat boiler (13) and the steam-water heat exchanger (14) are connected in sequence, and the steam-water heat exchanger (14) has a flue gas discharge port; A steam buffer tank (31) and a refrigeration unit are configured to be selectively connected to the waste heat boiler (13) and the steam-water heat exchanger (14) respectively, so that the refrigeration unit forms a two-stage cold flow supply structure when connected to the waste heat boiler (13) and the steam-water heat exchanger (14) respectively, and the steam buffer tank (31) forms a two-stage heat flow supply structure when connected to the waste heat boiler (13) and the steam-water heat exchanger (14) respectively.

2. The kiln cooling system according to claim 1, characterized in that, The refrigeration unit includes a steam-driven unit (21) and a hot water-driven unit (22). The steam-driven unit (21) is selectively connected to the waste heat boiler (13), and the hot water-driven unit (22) is selectively connected to the steam-water heat exchanger (14) to jointly form the secondary cold flow supply structure.

3. The kiln cooling system according to claim 2, characterized in that, The refrigeration unit also includes a first cold water buffer tank (23), which is provided with a first cold water inlet and a first cold water outlet. The first cold water inlet is connected to the outlet of the steam-driven unit (21), and the first cold water outlet is used to deliver cold water to the outside. And / or, the refrigeration unit further includes a second cold water buffer tank (24), the second cold water buffer tank (24) is provided with a second cold water inlet and a second cold water outlet, the second cold water inlet is connected to the outlet of the hot water drive unit (22), and the second cold water outlet is used to deliver cold water to the outside.

4. The kiln cooling system according to claim 3, characterized in that, The refrigeration unit also includes a chilled water supply path (25) and a kiln area cooling water path (26). The first cold water outlet is connected to the chilled water supply path (25) and the kiln area cooling water path (26) respectively, and the second cold water outlet is connected to the kiln area cooling water path (26). The cooling water path (26) in the kiln area is connected to at least one of the following: fan coil unit, heat sink, cold air box and dehumidification pipe.

5. The kiln cooling system according to claim 1, characterized in that, It also includes a flash evaporator (32), the outlet end of the waste heat boiler (13) is adapted to be selectively connected to the inlet end of the steam buffer tank (31), and the outlet end of the steam-water heat exchanger (14) is adapted to be selectively connected to the inlet end of the steam buffer tank (31) through the flash evaporator (32).

6. The kiln cooling system according to claim 1, characterized in that, It also includes a steam-using device (33) connected to the steam outlet of the steam buffer tank (31).

7. The kiln cooling system according to claim 1, characterized in that, The kiln structure includes at least two kiln bodies, and the at least two kiln bodies are respectively connected to the waste heat boiler (13).

8. The kiln cooling system according to claim 1, characterized in that, An exhaust fan (15) is connected to the flue gas emission outlet.

9. The kiln cooling system according to claim 1, characterized in that, A filter device is installed at the flue gas emission outlet; And / or, a flue gas duct is connected between the kiln structure and the waste heat boiler (13), and the flue gas duct is constructed as a double-layer pipe.

10. The kiln cooling system according to claim 1, characterized in that, It also includes a control module, which is configured to control the steam buffer tank (31) to be connected to the waste heat boiler (13) and the steam-water heat exchanger (14) respectively in the first seasonal mode, and to control the refrigeration unit to be connected to the waste heat boiler (13) and the steam-water heat exchanger (14) respectively in the second seasonal mode.

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